Method of manufacturing diamond die setting



Jan. 18, 1955 J. G. KRONOUER ET AL METHOD OF MANUFACTURING DIAMOND DIE SETTING Filed Jan. 16, 1951 INVENTORS JOHAN GEORGE KRONOUER JAN VAN DER WINDT AGENT United States Pat C6 ,699,692

THQ QEMANUFAQTURING. DIAMOND DIE SETTING Johan George Kronouer and Jan van der Windt, Eindhaven, Netherlands, assignors to Hartford National Bank and Trust Company, Hartford, Conn., as trustee Appiieation January 16, 1951, Serial No. 206,242

Claims priority, application Netherlands February 16, 1950 s 2 Claims. (Cl. 76-107) The present invention relates generally to methods of manufacturing settings for diamonds. More particularly, the invention relates to such methods wherein the diamond is to be housed in an envelope and provided with a bore, and to settings manufactured by such methods.

It is known to house a diamond die in an envelope, the diamond die having been provided previously with a bore, whereafter the assembly of envelope and diamond die is arranged in a setting. An important requirement of such a setting is that the envelope and the diamond die should tightly fit in the setting. A further requirement, often attempted to be improved upon, is that the setting should be as liquidtight as possible, so that the lubricant or the cooling agent used to lubricate or cool the product to be drawn engages the product drawn to the smallest possible extent. That is, for example, particularly important when copper wire is drawn, which, after having left the drawing device, is supplied without any intermediate operation to an enamelling or lacquering device.

According to the invention, both these requirements are fulfilled by a method of manufacturing a setting for a bored diamond die housed in an envelope which is characterized in that the envelope containing the diamond is arranged between two or more metal parts which are in contact with each other, these parts then being interconnected by buttwclding. In one embodiment of the invention, the metal parts preferably engage each other in a plane at right angles to the center line of the bore of the diamond, it not being necessary for the metal parts to engage each other throughout their surfaces. It is even desirable that said parts should engage only through a comparatively narrow edge, with which one or more of the metal parts is provided. As a matter of course, this contacting edge should completely embrace the envelope and the diamond. With a view to a simple manufacture, this contacting edge will preferably be shaped in the form of a circle.

According to a further embodiment of theinvention, it is advantageous, prior to the buttwelding operation, to arrange a foil between the envelope containing the diamond and one metal part, this foil being of metal which has a melting point lower than that of the metal of the metal parts and the envelope. It has been found in practice that in this manner a substantially tight setting is obtainable, it not being necessary for the envelope to fit exactly in one of the metal parts, since during the buttwelding operation the foil melts and fills up any cavities present. In one embodiment of the invention, the foil is preferably made of nickel-iron.

According to the invention, a setting for a bored diamond housed in an envelope is characterized in that this setting is made by one or more of the aforesaid methods.

In a further embodiment of the invention, the envelope of the diamond has a circular section in a direction at right angles to the center line of the bore of the diamond, at least one metal part of the setting having a cavity the diameter of which at least equals the diameter of the envelope.

In certain cases, the lubricant or the cooling agent for the product to be drawn contains an acid, or an acid is set free at the elevated temperature to which the said agent is exposed during the drawing operation. Other substances which affect metals to a greater or smaller Ratented Jan. 18, 1955 extent with prolonged contact may alsobe contained in the lubricant or the cooling agent; I'n'one embodiment or the invention, in order to avoid their'detrimental effect, the metal parts embracing the envelope and the diamond are made of rustless steel.

In order that the invention may be more clearly understood and readily carried into effect, it will now be described in detail with reference to the accompanying drawing, in which:

Fig. 1 is a plan view of a setting according to the invention; and

Fig. 2 is a sectional view of this setting.

Reference numeral 1 designates a circular metal part, preferably made of rustless steel. This metal part 1 is provided with a cavity 1' in which fits an envelope 2 containing a diamond 3 mounted on a plate 3'. The envelope 2 and the diamond 3 as well as plate 3 are preliminarily provided with a bore 8. A second metal part 4 also has a cavity 4 which accommodates the part of the envelope 2 containing the diamond 3 which is not embraced by the metal part 1. This metal part 4 is furthermore provided with an extending edge 5 which constitutes the contact surface between the parts 1 and 4. Between the upper edge of the envelope 2 and the inner side of the cavity in the part 4 is a space 6 in which a foil of nickel-iron 9 is arranged. The assembly, shown in Fig. 2, is now placed under a press and an electric current of, for example, 8 volts and 5000 amps, is led through the setting for about 0.1 sec. The result is that the extending edge 5 and the nickel-iron foil 9 are melted, so that on the one hand parts 1 and 4 are secured to each other and on the other hand the nickel-iron fills up any cavites which exist between the envelope 2 and the parts 1 an 4.

The pressure exerted must be so high that, during melting, the envelope 2 containing the diamond 3 is tightly enclosed in the cavities 1' and 6. When using the setting, the inlet and outlet sides appear to be separated in a liquid-tight manner. It is furthermore found, when using this method, that the diamond 3 is not damaged by the increase in temperature occurring, since the entire process is performed so rapidly that the buttwelding operation is completed before the diamond 3 assumes an inadmissible temperature. It is found that the envelope 2 remains comparatively cool so that inadmissible expansion is avoided and the diamond 3 remains rigidly embedded in the envelope 2.

While Fig. 2 shows two metal parts, it is obvious that the setting may be built up from more than two metal parts. It is to be understood that the foregoing modification and others which may occur to those skilled in the art upon contemplation of the present invention, may fall within the scope thereof as defined in the appended claims.

What we claim is:

l. A method of manufacturing a setting for a bored diamond die housed in a metal envelope comprising placing the envelope between two opposed metal discs which contact each other at their peripheries, spacing one of said metal discs from said metal envelope by a foil of metal having a melting point lower than that of both said metal discs and said metal envelope, passing a current through said metal discs and urging the discs together under pressure whereby the contacting surfaces are fused together to bond the discs together and the foil melts due to the heat generated.

2. A method of manufacturing a setting for a bored diamond die housed in a metal envelope comprising placing the envelope between two opposed metal discs, spacing one of said metal discs from said metal envelope by a foil of metal having a melting point lower than that of both said metal discs and said metal envelope, spacing said metal discs from each other by a meltable ridge, passing a current through said metal discs and urging the discs together under pressure whereby the contacting surfaces are fused together to bond the discs together and the foil and the ridge melt due to the heat generated.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Anderson Sept. 4, 1900 Lachman Nov. 24, 1908 5 Joyce Dec. 13, 1910 Dantsizen May 12, 1914 Murray Jan. 16, 1917 4 Singer Jan. 12, 1932 Harris May 22, 1934 De Bats Jan. 26, 1937 Romp Oct. 1, 1940 Ferrier Nov. 21, 1944 Scrantom Feb. 12, 1946 Duncan Mar. 6, 1951 

